Electrical terminal block assembly



Feb. 1, 1966 M. LAZAR ETAL ELECTRICAL TERMINAL BLOCK ASSEMBLY 2 Sheets-Sheet 1 Filed Dec. 1, 1960 FIGS INVENTORS MICHAEL LAZAR m ROBERT 6. KNOWLES ATTORNEY Feb. 1, 1966 M. LAZAR ETAL 3,233,209

ELECTRICAL TERMINAL BLOCK ASSEMBLY Filed Dec. 1, 1960 2 Sheets-Sheet 2 I I 4 I I l I A U J T \WYW IN VEN TOR. MICHAEL LAZAR By ROBERT amow s ATroRN Y United States Patent 3,233,209 ELECTRICAL TERMINAL BLOCK ASSEMBLY Michael Lazar, White Plains, N.Y., and Robert G.

Knowles, Norwalk, Conn., assignors to Burndy Corporation, a corporation of New York Filed Dec. 1, 1960, Ser. No. 73,013 4 Claims. (Cl. 339-198) This invention relates to connectors and more parltaifiularly to electrical terminal or connector block assem- Terminal blocks are Well known in the prior art for the purpose of removably interconnecting conductors by means of an internal connector or splice device. Commonly, the internal connector contains at least two sockets which receive plugs which are secured to the conductors to be interconnected. Preferably, the conductors or the plugs should be easily and readily inserted into the connector assembly, and make a secure mechanical end electrical connection therewith without the use of external tools; additionally, the connector or splice should be easily inserted into and insulated by its assembly housing, and be easily connected to other connectors in the assembly so that several conductors may thereby be readily commoned or electrically interconnected. It is desirable that the assembly housing be made of one piece construction, and be simply molded without elaborate core pin schemes; and that the connectors be made in a continuous process, such as a strip stamping. It is also desirable that the assembly housing provide a closed entry means for the connectors, that is, that the housing limits the diameter of probes which may be inserted into the connectors, to prevent oversize probes from distorting the connectors.

The prior art already includes several devices which to some degree meet these needs. Several of these devices include connector sockets in a continuous strip. A group of such sockets may be formed in the quantity needed and utilized to common a group of connectors.

The commoning strip, however, is outside the assembly housing and is uninsulated. This raises the problem of,

unintentional shorting or grounding of the conductors. Another type of these devices includes a substantially flat strip which may be cut to length. But this version does not integrally include a complete socket which will mechanically lock to the inserted conductor. Additional structure is required to fill this function.

It is, therefore, an object of this invention to provide a terminal or connector block assembly wherein the connectors may be easily and readily inserted into the insulating housing.

Another object of this invention is to provide an assembly wherein the connectors are provided in a continuous strip, wherein a group of connectors may be cut to length, and the entire cut-off group may be inserted into the housing, with the commoning elements also being insulated by the housing.

Yet another object is to provide a connector in the form of a socket which will mechanically lock to an inserted conductor without the use of external tools.

Still another object is to provide an interlock for terminal block housing which is adapted to interlock with similar housings to completely insulate the included connectors and to form a multilevel connector assembly.

Yet a further object of this invention is to provide an assembly housing which requires no core pins for the molding of the connector receiving body of the housing, and which will provide a closed entry means for the connectors contained therein.

A feature of this invention is a terminal block assembly comprising: an insulating housing having a plurality 3,233,209 Patented Feb. 1, 1966 of contact receiving bores therein, each bore having an opening in its side wall through which a connector may be transversely inserted while concurrently connected to an adjacent connector.

Another feature of this invention is an interlock of a plug with a chord-like shoulder and a socket with a chord-like detent.

Yet another feature of this invention is an end plate which may be clamped to a mounting channel to secure a plurality of housings therein.

These and other objects and features of this invention will become more apparent by reference to the following description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective exploded rear view of a terminal assembly embodying this invention;

FIG. 2 is a perspective front view of a plurality of terminal housings mounted together;

FIG. 3 is a side view of a terminal housing of FIG. 1;

FIG. 4 is a top cross-sectional view of the terminal housing taken at line 4-4 of FIG. 3;

FIG. 5 is a top cross-sectional view of the terminal housing taken at line 55 of FIG. 3;

FIG. 6 is a side cross-sectional view of the terminal housing taken at line 66 of FIG. 1;

FIG. 7 is a partial cross-sectional view of the interlock of the housing taken at line 7-7 of FIG. 6;

FIG. 8 is a side view in cross-section of the terminal connector shown in FIG. 1, the section being taken partially along the longitudinal medial axis, and partially through the connector interconnecting strip;

FIG. 9 is an end view of a strip of terminal connectors, such as is shown in FIG. 8;

FIG. 10 is a perspective exploded rear view of a second terminal assembly embodying this invention;

FIG. 11 is a perspective front view of two terminal housings of FIG. 10 mounted together;

FIG. 12 is a top view of the terminal housing of FIG. 10;

FIG. 13 is a side cross-sectional view of the terminal housing taken at 13-13 of FIG. 10;

FIG. 14 is a perspective view of a core pin diameter in a section taken along the detail of the mold utilized in forming the interlock of the housing shown in FIG. 7;

FIG. 15 shows a first endplate adapted for use with the assembly of FIG. 2; and

FIG. 16 shows a second endplate adapted for use with the assembly of FIG. 2.

As may be seen in FIGS. 1 through 9, the terminal assembly comprises an insulating housing 1 and a plurality of connectors 2. These connectors 2 may be formed in a continuous strip. The connector 2 may have a contact portion 3 formed at one or both ends and a connecting strip 4 joined to the adjacent connector to form the continuous strip, as may be seen in FIG. 9. As is shown in FIG. 8 the contact portion 3 may be formed into a socket, having two axially aligned pairs of opposed arms 5 which are adapted to encircle an inserted pin contact 6. A dimple 7 may be provided in the socket to engage an annular groove 8 or other surface discontinuity in the pin 6. As many connectors 2 as may be desired to be electrically interconnected in the same terminal assembly may be left physically interconnected in strip form by their connecting strips 4.

The insulating housing 1 includes a plurality of horizontally disposed longitudinal bores 9 to receive the connectors 2. Each bore 9 at its ends may have an opening 10 in its wall at the front side of the body; and at its middle has an opening 11 in its wall at the rear side of the body. When a plurality of housings are placed side by side, as shown in FIG. 2, the adjacent walls of the into the bore.

flanking housings cover the openings and 11 in the walls of the center housing bores, thus insulating the enclosed connectors from those of the flanking housings.

The connectors 2 are inserted transversely through rear side wall openings into the bores 9. One end of the connector may first be inserted at an angle into the bore 9 and its end tab 13 hooked behind the adjacent bore wall; then the connector may be pushed fully into the bore and the end tab 13 at the other end may be resiliently snapped behind its adjacent bore wall.

The bore projections 14 are disposed between and in engagement with the sockets 3 and serve to prevent longitudinal movement of the connector 2 in the bore 9. The end tabs ,13 engaging the inner surface of the bore serve to prevent transverse movement of connector out of the bore.

The rear side of the housing may be undercut between adjacent bores, as at 15, .to accommodate the connecting element 4. Thus a plurality of electrically and mechani- -cally commoned connectors may inserted into the housing. Adjacent connectors may be made electrically independent by cutting away the connecting elements 4, to ensure an adequate space between adjacent independent connectors. Any number of bores may be provided in each housing, and any combination of independent and commoned connectors may be inserted into the bores.

If it is desired to utilize the housing 1 to provide a constricted entryfor the mating pin contacts 6, commonly known as a closed entry feature for the connectors 2, it is merely necessary to mold the housing with end openings 10 of smaller transverse dimension than the middle openings 11 and the sockets 3 contained therein. Where the housing is stacked alongside a similar housing or an endplate 12, a complete closed entry means will be provided. Although this closed entry means will not include a rigid and unbroken annulus, it will still provide a satisfactory means for preventing oversize probe insertion.

Since the connectors 2 are transversely inserted through middle openings '11, rather than axially through end openings 10, the end openings can actually be molded to any .size and section desired including a closed entry having an unbroken periphery, without being limited by the connector size and section.

be provided with a plurality of vertically disposed longitudinal bores 109. Each bore 109, at its top end, may have an opening 110 in its side wall to the front side of the body; and at its middle, has an opening 111 in its side wall to the rear side of the housing.

The connector 102 for insertion in the vertically bored housing 101 is similar to previously described connector 2 but has a contact or socket 3 at one end only. A horizontal bore connector may be converted into a vertical bore connector by cutting off one socket 3, as at point A on FIG. 8.

The vertical bore connector 102 is transversely inserted into the bore 109 through the side wall opening 111. The

connector 102 may be inserted at an angle so that vestigial tab 113passes into the bore 109 and engages the inner surface of the bore, and then the connector is pushed completely into the bore with end tab 13 being snapped The rear side of the housing is undercut between adjacent bores, as at 115, to accommodate the connecting element 4. The bore projection 114 is disposed in engagement with the socket 3, and serves to prevent downward longitudinal movement of the connector in the bore; while connecting element 4 engages the undercut and serves to prevent upward longitudinal movement. The end tab 13 and vestigial tab 113 engaging the inner surface of the bore serve to prevent transverse movement of the connector out of the bore.

shoulders 22 formed therein by opposed chord flats 23; and a mating socket 24 of circular cross-section having two detents formed therein by opposed chord-ribs 25. The body is made of a resilient insulating material such as plastic, and a pin 21 may be forced into a socket 24, interlocking the shoulders 22 and ribs 25; and then subsequently the pin and socket may be pried apart.

As is seen in FIG. 14, the pin with its chord-flats, and the axially aligned socket with its chord-ribs may be concurrently molded by use of a suitable core pin 26 in a mold 27. The core pin 26 is formed of rod stock. The rod forms the socket 24, while two notches 28 cut into the rod form the two plastic ribs 25 in the socket. The end of the rod 26 has two flats 29 milled therein perpendicular to the two notches 28 the plastic is excluded from the volume occupied by remaining section of the rod, and the absence of plastic resulting 'from the mating of the flatted pin and the mold forms the void providing the chord flats 23 with their shoulders 22.

It will be seen that by this design and method of molding, the entire housing can be molded in an economical two piece or printing-line mold; two simple core pins being used to form the interlock means. By the use of connector receiving bores having side openings, no side pull core pins are neceessary to form the bores, the cope and drag of the mold themselves having projections to form the bores. By the use of the novel core pins, discussed above, the flats 23 can be formed as part of the molding operation, without any need for more elaborate milling operations.

The housings may be disposed in a standard channel 17 shown in dotted lines, legs 18 being provided for this purpose; see FIG. 2.

The plurality of housings may be secured in the channel by a suitable end plate which will also cover the bore side wall openings 10 and 11 in the outermost housings. FIG. 15 illustrates an end plate 151 having a pair of legs 152 for insertion in channel 17. A cam 153 with ahandle 154 is pivoted at 155 to plate 151, and on being rotated is adapted to press on ,the baseof channel 17 or to dig into it and to clamp legs 152 to the underside of the channel.

A second embodiment of an endplate is shown in FIG. 16. An upper member 161 is slidably mounted to a lower member 162 having legs 163. A draw screw 164 is adapted to draw the two members together, clamping them to channel 17.

If it is so desired, channel arms 19, as shown in dotted lines in FIG. .1, may be formed on top of each housing 2 to permit vertical stacking of the housing. Suitable crossstrips (not shown) may be provided through arches 20 and the top-most arms '19, to maintain the rigidity of the groups.

Further, if it is so desired,-horizontally and vertically bored housings may be intermixed and interlocked together, since the housings can be made with standardized outer dimensions and mutual interlocks. Although adjacent intermixed housings may not provide a complete cover for each others side openings, still the side walls space the adjacent connectors apart and prevent unintentional commoning between the connectors of adjacent intermixed housings.

We claim:

1. A terminal block assembly, comprising: a one-piece insulating housing having a first longitudinally extending groove of given length in one side thereof forming a pair of longitudinally spacedapart opposed end walls; a second longitudinally extending groove in said housing axially aligned with but facing in a direction opposite to said first groove and axially extending through one edge of said housing; one of said end walls ,of said first groove having an opening therethrough forming a connector-engaging recess and providing axial access to said first groove from said second groove; the other of said end walls having a connector-engaging recess therein; a one piece electrical connector adapted to be transversely inserted into said first groove, including a longitudinally extending base portion of substantially said given length adapted to be electrically connected to an external circuit and having a pair of transversely extending arm portions forming a split-sleeve electrical socket contact proximate one end thereof; said base portion including longitudinally extending resilient tab subportions at each end thereof adapted to engage said end wall recesses to interlock said connector to said housing.

2. A terminal block assembly according to claim 1 further including a plurality of said spaced-apart first and second grooves disposed in substantially parallel side-byside relation in said housing, wherein a plurality of said electrical connectors are provided and are interconnected by transversely extending integral interconnecting subportions extending from the base portions of said connectors, and said housing is provided with notches between said plurality of grooves to receive said interconnecting subportions.

3. The terminal block assembly of claim 1, wherein: said connector includes an additional pair of transversely extending arm portions forming another split-sleeve socket proximate the other end of said connector base portion; said housing includes a third longitudinally extending groove axially aligned with said first groove at the said other end thereof and axially extending through an edge of said housing; and said other end wall of said axial access from said third groove to said first groove.

4. The terminal block assembly of claim 1, wherein: the sides of said housing are shaped to mate with other identical blocks in intimate side-by-side relationship, and said housing includes at least one interlocking projection on one side thereof and one interlocking recess on the other side thereof adapted to interlock with the projection of a mating housing.

References Cited by the Examiner UNITED STATES PATENTS 1,641,923 9/ 1927 Davis 264276 1,697,814 1/1929 Forbes 24141 2,225,632 12/1940 Herman 1842 2,397,102 3/1946 Graham 339-198 2,463,826 3/ 1949 Thacker 339-198 2,635,312 4/1953 McCullough 339-272 2,683,506 7/1954 Immel et al. 339198 2,688,123 8/1954 Benham et a1 339-176 2,816,341 12/1957 Prest 24221 2,888,661 5/1959 Gilbert 339274 2,911,615 11/1959 P-opejoy et al 339-198 2,922,139 1/1960 Ustin 339198 2,925,577 2/1960 Cetran et a1 339198 2,981,922 4/ 1961 Van Valkenburg et a1. 339198 2,985,861 5/1961 Rogolf et al. 229198 3,005,180 10/1961 Dreher 339198 FOREIGN PATENTS 964,618 5/1957 Germany.

JOSEPH D. SEERS, Primary Examiner. 

1. A TERMINAL ASSEMBLY, COMPRISING: A ONE-PIECE INSULATING HOUSING HAVING A FIRST LONGITUDINALLY EXTENDING GROOVE OF GIVEN LENGTH IN ONE SIDE THEREOF FORMING A PAIR OF LONGITUDINALLY SPACED-APART OPPOSED END WALLS; A SECOND LONGITUDINALLY EXTENDING GROOVE IN SAID HOUSING AXIALLY ALIGNED WITH BUT FACING IN A DIRECTION OPPOSITE TO SAID FIRST GROOVE AND AXIALLY EXTENDING THROUGH ONE EDGE OF SAID HOUSING; ONE OF SAID END WALL OF SAID FIRST GROOVE HAVING AN OPENING THERETHROUGH FORMING A CONNECTOR-EN GAGING RECESS AND PROVIDING AXIAL ACCESS TO SAID FIRST GROOVE FROM SAID SECOND GROOVE; THE OTHER OF SAID END WALLS HAVING A CONNECTOR-ENGAGING RECESS THEREIN; A ONEPIECE ELECTRICAL CONNECTOR ADAPTED TO BE TRANSVERSELY INSERTED INTO SAID FIRST GROOVE, INCLUDING A LONDITUDINALLY EXTENDING BASE PORTION OF SUBSTANTIALLY SAID GIVEN LENGTH ADAPTED TO BE ELECTRICALLY CONNECTED TO AN EXTERNAL CIRCUIT AND HAVING A PAIR OF TRANSVERSELY EXTENDING ARM PORTIONS FORMING A SPLIT-SLEEVE ELECTRICAL SOCKET CONTACT PROXIMATE ONE END THEREOF; SAID BASE PORTION INCLUDING LONGITUDINALLY EXTENDING RESILIENT TAB SUBPORTIONS AT EACH END THEREOF ADAPTED TO ENGAGE SAID END WALL RECESSES TO INTERLOCK SAID CONNECTOR TO SAID HOUSING. 